An individual (usually a woman) who lives by the radical proposition that they should have sex with whomever they want and not give a shit what random judgmental twats who seem to think it's any of their business think.

"Man, Brighton is absolutely full of slags, and that's just the men. ;)"

A female who is a bit too available, sexually. She often presents herself in too little clothing and, in some extreme cases of slaggery, she has been known to perform oral sex on boyfriends that are not her own.

Do you really think that woman is a slag?

Yes, i saw her with a few different men in the span of a bakers dozens worth of days.